The poses should snap together for you with no issues, but if you need to tweak them, the use of the moveobjects on cheat using the alt key on your keyboard to position them could be used.

Pose 10- hanging upside down is a pose you can hang from many different objects, so I gave it no definite height. The use of the one more slot package from Mod the Sims will be needed to raise of lower the sim to the height of the object you want the child to hang from. Found here: http://modthesims.info/d/428179

Pose set is pose list compatible, however if you need the codes they are as follows:

c_bmit_childplay2_pose1
c_bmit_childplay2_pose2
c_bmit_childplay2_pose3
c_bmit_childplay2_pose4
c_bmit_childplay2_pose5
c_bmit_childplay2_pose6
c_bmit_childplay2_pose7
c_bmit_childplay2_pose8
c_bmit_childplay2_pose9
c_bmit_childplay2_pose10
c_bmit_childplay2_pose11

Credits: TSR for their patience and great work!